Buggy code:
private acceptTypes ( Scope scope ) { } public void acceptUnresolvedName ( char [ ] name ) { } private void addExpectedType ( TypeBinding type , Scope scope ) { } private void addForbiddenBindings ( Binding binding ) { } private void addUninterestingBindings ( Binding binding ) { } private final boolean areParametersCompatibleWith ( TypeBinding [ ] parameters , TypeBinding [ ] arguments , boolean isVarargs ) { } private void buildContext ( ASTNode astNode , ASTNode astNodeParent , CompilationUnitDeclaration compilationUnitDeclaration , Binding qualifiedBinding , Scope scope ) { } private void buildTokenLocationContext ( InternalCompletionContext context , Scope scope , ASTNode astNode , ASTNode astNodeParent ) { } void checkCancel ( ) { } private boolean complete ( ASTNode astNode , ASTNode astNodeParent , ASTNode enclosingNode , CompilationUnitDeclaration compilationUnitDeclaration , Binding qualifiedBinding , Scope scope , boolean insideTypeAnnotation ) { } public void complete ( ICompilationUnit sourceUnit , int completionPosition , int pos , ITypeRoot root ) { } public void complete ( IType type , char [ ] snippet , int position , char [ ] [ ] localVariableTypeNames , char [ ] [ ] localVariableNames , int [ ] localVariableModifiers , boolean isStatic ) { } private void completionOnBranchStatementLabel ( ASTNode astNode ) { } private void completionOnClassLiteralAccess ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnExplicitConstructorCall ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnFieldName ( ASTNode astNode , Scope scope ) { } private void completionOnFieldType ( ASTNode astNode , Scope scope ) { } private void completionOnJavadocAllocationExpression ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnJavadocFieldReference ( ASTNode astNode , Scope scope ) { } private void completionOnJavadocMessageSend ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnJavadocParamNameReference ( ASTNode astNode ) { } private void completionOnJavadocQualifiedTypeReference ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnJavadocSingleTypeReference ( ASTNode astNode , Scope scope ) { } private void completionOnJavadocTag ( ASTNode astNode ) { } private void completionOnJavadocTypeParamReference ( ASTNode astNode ) { } private void completionOnKeyword ( ASTNode astNode ) { } private void completionOnLocalOrArgumentName ( ASTNode astNode , Scope scope ) { } private void completionOnMarkerAnnotationName ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnMemberAccess ( ASTNode astNode , ASTNode enclosingNode , Binding qualifiedBinding , Scope scope , boolean insideTypeAnnotation ) { } private void completionOnMemberValueName ( ASTNode astNode , ASTNode astNodeParent , Scope scope , boolean insideTypeAnnotation ) { } private void completionOnMessageSend ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnMessageSendName ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnMethodName ( ASTNode astNode , Scope scope ) { } private void completionOnMethodReturnType ( ASTNode astNode , Scope scope ) { } private void completionOnParameterizedQualifiedTypeReference ( ASTNode astNode , ASTNode astNodeParent , Binding qualifiedBinding , Scope scope ) { } private boolean assistNodeIsExtendedType ( ASTNode astNode , ASTNode astNodeParent ) { } private void completionOnQualifiedAllocationExpression ( ASTNode astNode , Binding qualifiedBinding , Scope scope ) { } private void completionOnQualifiedNameReference ( ASTNode astNode , ASTNode enclosingNode , Binding qualifiedBinding , Scope scope , boolean insideTypeAnnotation ) { } private void completionOnQualifiedTypeReference ( ASTNode astNode , ASTNode astNodeParent , Binding qualifiedBinding , Scope scope ) { } private void completionOnSingleNameReference ( ASTNode astNode , ASTNode astNodeParent , Scope scope , boolean insideTypeAnnotation ) { } private void completionOnSingleTypeReference ( ASTNode astNode , ASTNode astNodeParent , Binding qualifiedBinding , Scope scope ) { } private char [ ] [ ] computeAlreadyDefinedName ( BlockScope scope , InvocationSite invocationSite ) { } private void computeAlreadyDefinedName ( FieldBinding [ ] fields , Scope scope , boolean onlyStaticFields , ReferenceBinding receiverType , InvocationSite invocationSite , ArrayList result ) { } private void computeAlreadyDefinedName ( SourceTypeBinding receiverType , ClassScope scope , boolean onlyStaticFields , InvocationSite invocationSite , ArrayList result ) { } int computeBaseRelevance ( ) { } private void computeExpectedTypes ( ASTNode parent , ASTNode node , Scope scope ) { } private void computeExpectedTypesForAllocationExpression ( ReferenceBinding binding , Expression [ ] arguments , Scope scope , InvocationSite invocationSite ) { } private void computeExpectedTypesForMessageSend ( ReferenceBinding binding , char [ ] selector , Expression [ ] arguments , ReferenceBinding receiverType , Scope scope , InvocationSite invocationSite , boolean isStatic ) { } private void computeExpectedTypesForMessageSendForInterface ( ReferenceBinding binding , char [ ] selector , Expression [ ] arguments , ReferenceBinding receiverType , Scope scope , InvocationSite invocationSite , boolean isStatic ) { } private Scope computeForbiddenBindings ( ASTNode astNode , ASTNode astNodeParent , Scope scope ) { } private char [ ] computePrefix ( SourceTypeBinding declarationType , SourceTypeBinding invocationType , boolean isStatic ) { } private int computeRelevanceForAnnotation ( ) { } private int computeRelevanceForAnnotationTarget ( TypeBinding typeBinding ) { } int computeRelevanceForCaseMatching ( char [ ] token , char [ ] proposalName ) { } private int computeRelevanceForClass ( ) { } private int computeRelevanceForEnum ( ) { } private int computeRelevanceForEnumConstant ( TypeBinding proposalType ) { } private int computeRelevanceForException ( ) { } private int computeRelevanceForException ( char [ ] proposalName ) { } private int computeRelevanceForExpectingType ( char [ ] packageName , char [ ] typeName ) { } private int computeRelevanceForExpectingType ( TypeBinding proposalType ) { if ( ( ( this . expectedTypes ) != null ) && ( proposalType != null ) ) { int relevance = 0 ; for ( int i = 0 ; i <= ( this . expectedTypesPtr ) ; i ++ ) { if ( ( ( ( this . expectedTypesFilter ) & ( CompletionEngine . SUBTYPE ) ) != 0 ) && ( proposalType . isCompatibleWith ( this . expectedTypes [ i ] ) ) ) { if ( ( CharOperation . equals ( this . expectedTypes [ i ] . qualifiedPackageName ( ) , proposalType . qualifiedPackageName ( ) ) ) && ( CharOperation . equals ( this . expectedTypes [ i ] . qualifiedSourceName ( ) , proposalType . qualifiedSourceName ( ) ) ) ) { return RelevanceConstants . R_EXACT_EXPECTED_TYPE ; } relevance = RelevanceConstants . R_EXPECTED_TYPE ; } if ( ( ( ( this . expectedTypesFilter ) & ( CompletionEngine . SUPERTYPE ) ) != 0 ) && ( this . expectedTypes [ i ] . isCompatibleWith ( proposalType ) ) ) { if ( ( CharOperation . equals ( this . expectedTypes [ i ] . qualifiedPackageName ( ) , proposalType . qualifiedPackageName ( ) ) ) && ( CharOperation . equals ( this . expectedTypes [ i ] . qualifiedSourceName ( ) , proposalType . qualifiedSourceName ( ) ) ) ) { return RelevanceConstants . R_EXACT_EXPECTED_TYPE ; } relevance = RelevanceConstants . R_EXPECTED_TYPE ; } <START_BUG> if ( ( ( this . unitScope ) != null ) && ( this . unitScope . isBoxingCompatibleWith ( this . expectedTypes [ i ] , proposalType ) ) ) { <END_BUG>

Fix:
if ( ( ( this . unitScope ) != null ) && ( this . unitScope . isBoxingCompatibleWith ( proposalType , this . expectedTypes [ i ] ) ) ) {